24 Mt Diablo Cir
San Rafael 94903 · Lucas Valley · Unincorporated Marin · Coordinates: 38.02956, -122.57020
Executive Verdict · Public-Records Synthesis
Zoned R1-B-LV in Unincorporated Marin with likely ADU & SB 9 infill eligibility and mapped CAL FIRE high fire hazard severity zone (local responsibility area) due diligence; benchmark value $1,453,000 ($1,279,000–$1,627,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1-B-LV supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 13,024 sq ft lot. Local precedent is active with 1 ADU permit within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$20,160 contributory est.)
Public building records show issued construction/renovation work on this parcel (5 total permits, latest Jul 30, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! Mapped flood awareness zone (Zone X: minimal flood hazard)
all of the lot of the parcel intersects Zone X: minimal flood hazard. Outside mandatory federal SFHA insurance rules, but check local drainage and finished-floor requirements.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! CAL FIRE High Fire Hazard Severity Zone (Local Responsibility Area) (all of the lot of lot)
Located in a mapped Fire Hazard Severity Zone. Expect Chapter 7A ignition-resistant building standards, defensible-space inspections, and stricter property insurance underwriting.
Source: CAL FIRE FHSZ (map Mar 24, 2025)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: New home (0.2 mi SE, entitled). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
- ! Year 1 Prop 13 tax reset (~$17,160/yr at $1,453,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,430/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Parcel & Assessor
- Lot size:
- 13,024 sq ft (0.30 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 24 MT DIABLO CIR
Zoning & Land Use
R1-B-LV — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B-LV (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1-B-LV, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-B-LV, a single-family residential zone. The lot is 13,024 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- High Fire Hazard Severity Zone (Local Responsibility Area) (all of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0289D, effective May 4, 2009
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,279,000 – $1,627,000 · Status: Off market
HUD Small Area FMR (ZIP 94903) · FY 2026
Studio $2,880 · 1BR $3,450 · 2BR $4,180 · 3BR $5,340 · 4BR $5,530
Developments Deserving Closer Investigation & Active Area Builders
- New home (Entitled)0.2 mi SE
In "Entitled" for 2.9 yr (since Dec 7, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- New home (Entitled)0.2 mi SE
In "Entitled" for 3.3 yr (since Jul 10, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- New home (Entitled)0.2 mi SE
In "Entitled" for 3.8 yr (since Jan 14, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- New home (Entitled)0.2 mi SE
In "Entitled" for 5.1 yr (since Sep 23, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Entity-resolved builders & contractors in ½ mile: Semper Solaris (2 on parcel, 2 in ½ mi · Electrical / panel); Tesla Energy (2 on parcel, 2 in ½ mi · Electrical / panel); Silveira Enterprise (1 on parcel, 1 in ½ mi · Electrical / panel); Owner Builder (19 in ½ mi · Remodel / interior alteration); Tim Lawlor Construction (6 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (5 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B47682 | Electrical / panel | Issued | Iss. Jul 30, 2026 | $20,000 | New Circuits / Outlets, Service Upgrade |
| 166739 | Electrical / panel | Issued | Iss. Jan 4, 2021 | $13,000 | Main Panel Upgrade & 200a Meter Disconnect |
| 166738 | Solar / battery storage | Issued | Iss. Jan 4, 2021 | $75,264 | 14.06kw Rooftop Photovoltaic & Energy Storage System |
| 163087 | Electrical / panel | Issued | Iss. Oct 31, 2019 | $2,000 | Main Panel Upgrade |
| 163086 | Solar / battery storage | Issued | Iss. Oct 31, 2019 | $5,600 |